The field of the present invention is engines and particularly small, lightweight engines.
Small, lightweight engines have found recent utility in such applications as remotely piloted vehicles, ultra-light aircraft and the like. In such uses, the forward extension of the engine is often possible to convert a composite engine from two to four and even to six cylinders. The number of cylinders would specifically depend upon the load and power required.
Engines have been developed which are capable of being expanded from one or two cylinders to a greater number of cylinders through coupling of crankcases end to end. In doing so, often replacement crankshafts are required to accommodate the increased number of crank pins. Additionally, bearings are often incorporated into each end of each crankcase component. Such designs are truly nothing more than hooking multiple engines together. Naturally, this can create excessively lengthy engines and necessarily increase the weight of both the engines in general and the crankshaft in particular. Consequently, the utility of such devices can be diminished.